Psychological Predictors of Threat Recognition and Bystander Intervention: A Warning Behavior Simulation

Bystanders often observe warning behaviors before campus violence occurs, yet the traits determining whether they recognize danger and intervene remain poorly understood. This study used an agent-based simulation of 500 virtual agents, calibrated from meta-analytic data on empathy, social connectedness, emotion regulation, and stigma, to model perceived threat and willingness to intervene across six warning behaviors from the threat assessment literature. The four traits alone explained 17.5% of the variance in intervention willingness ( R 2 = .175); adding perceived threat as a mediator raised this to 36.6% (Δ R 2 = .191), with bootstrapped mediation confirming this for all four. Stigma was the only negative predictor, and the strongest barrier to intervention. Pathway elicited the highest threat perception and willingness, Grievance the lowest; high-ambiguity scenarios produced lower ratings on both outcomes than low-ambiguity scenarios. These results suggest campus programs should pair stigma reduction and threat recognition training with efforts to encourage bystander action.